• Journal of the Korean Society of Radiology
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• v.11 no.5
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• pp.413-421
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• 2017

Mammography, the basic test for finding and treating increased breast cancer, gives the anxiety of cancer and radiation exposure to most women. In addition, it gave very severe compression pain, so we studied the degree of pain and tried to reduce the pain. The purpose of this study is to compare and analyze the modified imaging technique and the basic imaging technique based on clinical experience, respectively. The subjects of this study were 160 women from 30 to 60 years old who visited to Seoul Boramae Hospital operated by Seoul National University Hospital from February to March 2017 for breast screening. Modified 80 persons and 80 persons were divided into two groups, and each group was asked to fill out questionnaires sequentially without knowing the subjects. The first method is a modified method in which an automatic pedal is divided into four or more presses, a manual pressure is used together, and an attitude is described in detail. Secondly, we used only the automatic pedal compression method and press it within 1-3 times. In the mean of the pain distribution, the experimental group (modified method) was 2.49 and the control group (basic method) had an average of 4.86, which showed 48.8% less pain. In this modified method, the pain scores of the experimental group were lower than those of the control group, and the degree of the pain was statistically significant.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.1
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• pp.159-164
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• 2016

This paper reports the load factor logic design for a fly-by-wire helicopter flight envelope protection. As a helicopter is very complex system with a rotor, fuselage, engine, etc., there are many constraints on the flight region. Because of these constraints, pilots should consider them carefully and have a heavy workload, which causes controllability degradation. In this respect, automatic logic is needed to free the pilot from these considerations. As one of these logics, the flight envelope protection logic for the load factor of a FBW helicopter was designed. The flight to exceed the load factor is caused by an abrupt pitch cyclic stick change. In this scheme, the load factor limit logic was added between the pilot stick command block and pitch attitude command block. From the current load value, the available attitude range was calculated dynamically and simulated on the helicopter simulator model to verify the performance. A comparison of the simulation results at the hovering and forward speed region with and without applying the load limiting logic showed that the load factor limit was exceeded more than 20% when the logic was not applied, whereas with the load factor limit logic the load factor was within the limit. In conclusion, a dynamically allocated limitation logic to helicopter FBW controller was verified by simulation.

• Korean Journal of Remote Sensing
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• v.33 no.2
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• pp.231-242
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• 2017

Monitoring of facilities such as roads, dams and bridges is important for their long-term sustainable usage. It has usually suffered with safety and cost problems, which makes more frequent monitoring difficult. As an efficient and economicalsolution to these problems, one may consider the use of smartphone to capture the status of the facilities. To derive quantitative analysis results with the smartphone images for facility monitoring, one should first rectify the images in a way as automatic and economical as possible. In thisstudy, we propose such a rectification method, which rectifiessmartphone images acquired from arbitrary locations based on reference images.In the proposed method, we determine the camera extrinsic parameters of each smartphone images using the reference imagesrather than ground control points, and project the image to the target surface of the facility based on the determined camera parameters. The method were applied to test data acquired from a small dam toward water-area facility monitoring. The experimental results showed that the camera extrinsic parameters were determined with the accuracy of 5 cm and $0.28^{\circ}$ in the position and attitude. The accuracy of the distance measured from the rectified image was evaluated to 10 cm. With the rectified images, one can accurately determine the location and length of the target objects required for facility monitoring.